Just a quick comparison (GB vs ASRock):
Two USB 2.0 instead of two 2.0 and two 3.0
Two ethernet instead of three (one dedicated to IPMI)
No PS/2
Five SATA instead of six
Three fan headers instead of two
It looks like there might be an internal USB port like the ASRock has, but it's not documented in the manual.
That's what stood out to me anyway.
Unless it's significantly cheaper, I'm not seeing an advantage. Note that there's also a C224 version of the ASRock that drops some of the SATA ports to v2 instead of v3 and is cheaper than the C226.
It's nice to see some more entries in the mini-ITX space, but without a price it's hard to say how this one stacks up.
